Product thereof



Patented Sept. 29, 1942 OFFICE MET-HOD OF MAKINGADHESIVES AND PRODUCT THEREOF Davis Miller Wood, Tacoma, Wash.

No Drawing. Application February 28, 1939, Serial No. 258,946

11 Claims. (01. 106-154) My invention relates to an improvement in the method of making an adhesive and the product thereof. My invention will be described in its relation to the manufacture of veneer panels.

U. S. Patent No. 1,981,972, entitled Sulphated condensation products of fatty acids with monoethanolamine, was issued in 1933, and I have discovered that by means of using the product made according to said patent in the manner hereinafter set forth I.have made a great improvement in a basic glue (as hereinafter defilled). The product of said Patent No. 1,981,972 I will hereafter define as the sulphated product of the condensation reaction of the fatty acids containing a substantial quantity of C1: and C14 acids with monoethanolamine, and when using said term I mean to embrace and describe such substances as Intramine P. C., Intramine D. X. and Intramine Y, any one of which is a sulphated product of the condensation reaction of fatty acids containing a substantial quantity of C12 and C14 acids with monoethanolamine. To illustrate the method of making the Intramines above mentioned, I give the following example, using the naturally occurring coconut fatty acids, viz:

210 pounds coconut fatty acids having an average molecular weight of 210 is heated with 67 pounds of monoethanolamine for a few hours in a still until the acid number determined in alcohol sinks to below 5, the water evolved being allowed to escape. The distillate of water and excess monoethanolamine amounts to about 19 pounds. The mass on cooling sets to a pale yellow wax-like substance, having a solidification point of 60-65 C., and may be sulphonated directly. This product is slightly soluble in water. This product may be subjected to the action of sulphuric acid in the following manner;

To 100 pounds of sulphuric acid monohydrate at Bil-33 C. is added, while stirring and cooling, 100 pounds of the condensation product of the coconut fatty acids and monoethanolamine.

After the addition is complete, and the mass completely homogeneous, tests are made to determine the water solubility. As soon as the solubility is complete, the mass is mixed with 75 pounds of ice and neutralized wh le cooling with sufficient 50% caustic soda to bring the whole to a neutral reaction to litmus. The excess sulphuric acid may also be separated by slight dilution or salted out. This treatment results as nearly 'as can be ascertained in the formation of a predominant quantity of the sulphuric esters in which the sulphur atom is joined to the compound by an oxygen linkage and possibly of some slight wanglue adhesiveness, a high water resistant bond, and

of substantially uniform viscosity, and a glue which will avoid much checking and surface stain when applied to thin wood surfaces, and a glue which will reduce the cost while attaining great wet and dry strength.

All of these qualities appertain to a glue or glues made by my discovery, and to a far greater extent than to glues heretofore made which employ vegetable flour of a high protein content, as herein described, as a predominant ingredient in quantity.

Seed base, as used herein, is the flour or meal made from vegetable seed. beans or nuts from which a large portion of the oil has been extracted, and which flour or meal contains from 35% to 50%, or thereabouts, of protein.

When there is added to, or substituted for a part'of, a "seed base, animal proteins, such as casein or blood albumen. I will designate the composition as a blend base.

I mention soya bean flour and peanut flour as among the flours which I can use, and coming within the definition of a seed base, but other vegetable flours having substantially the protein content above mentioned can be used. To either the seed base" or the blend base is added the following:

Lime, caustic soda, sodium silicate, carbon bisulphide or its equivalent, or carbon bisulphide and carbon tetrachloride, which I will hereafter refer to as carbon bisulphide-tetrachloride dope, and to them may be added alkali metal salt which when used with lime by double decomposition produces causticity; and pine oil, and water. The above mentioned ingredients, or the proportions of the above mentioned ingredients, may be varied, and the glue made therefrom come within the term basic glue".

Glues comprising the foregoing "seed base or blend base,and chemicals last above mentioned I will call basic glue. To illustrate a basic formula now very commonly used in the manufacture of veneer panels the following formula is given:

Another formula for basic glue" is substantially as follows:

Pounds Soya bean flour 93.5 Trisodium phosphate 1.5 Sodium carbonate 5 Lime to Caustic soda 4.5 Silicate of soda 30 Carbon bisulphide-tetrachloride dope 2 Aldehyde compound, made according to Patent 1,950,060 2 Water 350 to 365 Similar formulae employ peanut flour in place of some or all of the soya bean flour, and some have a percentage of casein or blood albumen substituted for a like percentage of flour, and some have pine oil added.

My invention is an improvement on all such basic glue," and I do not claim herein to have invented any such basic glue. When the term basic glue" is used herein and in the claims, I mean any one of the basic glue formulae mentioned herein or the basic glue as generally described herein.

I have discovered that by incorporating in a basic glue Intramine P. C., Intramine D. X., or Intramine Y, (any one of which I have, in the claims, referred to as a sulphated product of the condensation reaction of fatty acids containing a substantial quantity .of C1: and C14 acids with monoethanolamine) in the proportion of about 0.05% to 2% of the weight of the seed base" or blend base in the basic glue," a decided change takes place in the basic glue, in that the texture of the basic glue is changed from a grainy nature, resembling bean soup, to a smooth and ungrainy structure, resembling varnish in texture; the applicability of the glue made according to my invention to veneers in amechanical spreader is facilitated; the strength of the glue bond is increased as hereinafter stated; the working life of my "improved glue is lengthened approximately three times that of "basic glues. As hereinafter stated the quantity of seed base" or blend base to spread 1000 square feet of 3-ply panels is less than required to spread 1000 square feet of 3-ply panels when using the basic glue; and the staining and checking of the panels is reduced.

Such basic glue requires from 27 lbs. to 30 lbs. of seed base" or blend base in a basic glue" to spread 1000 square feet of 3-ply panels to get its maximum stick; whereas, my improved glue made according to my invention, as hereinafter set forth,.wil1 spread 1000 square feet of 3-ply panels with some lbs. to 26 lbs. of seed base" or blend base to get its maximum stick.

The working life of glue means the time during which the glue retains substantially its maximum strength and spreadability after it is made up. In ordinary plant practice a batch of glue is made up and before the last of such a. batch is used to spread the panels there elapses from 30 minutes to an hour and a half, and frequently more. This is in addition to the time required to make up a stack of panels after the glue is spread on the first panel which goes into the stack, the first spread panel being on the bottom of the stack.

In veneer plant practice panels made up of veneer spread with glue, are stacked up preparatory to being put into a press. Pressing is required to bring the wood surfaces into intimate contact with the glue which has been applied to hold together the veneercomposing the panels. Pressure must be exerted before the glue in the lower panels of the stack loses any substantial part of its adhesive qualities, failing which there is produced an inferior or faulty panel or panels Y in the lower part of the stack. In plant practice frequently more than 30 minutes is desirable to make up a stack of panels for pressing. About 10 minutes after a basic glue is applied to the panels the adhesive quality thereof commences to decrease and the ordinary time after "basic glue" is applied which is considered safe to insure a good joint before applying pressure is not over 30 minutes after the glue is spread upon the veneer panels. Glue made according to my improved glue" and zinc sulphate glue inventions (as hereinafter defined) retains its adhesive qualities longer (that is, the working life), and is as strong or stronger after the panels are spread for 30 minutes and before pressure than a basic glue is after standing 10 minutes in the panels. Thus the working life of glue made according to my invention far exceeds the working lift of a basic glu'e. This important'improvement in working life has been long desired by manufacturers of veneer panels, and has been accomplished by my invention.

To obtain the maximum adhesion of a basic glue it has been heretofore required that the seed base be ground to 110 mesh or finer, it having been found that the finer the seed base is ground the better adhesion is obtained in a basic glue." By means of my invention I have found that a seed base ground from to mesh produces a glue superior to a basic glue" employing a seed base ground to mesh in its adhesive qualities, and ease of spreading, and otherwise, as herein pointed out. Thus there is a saving in time and expense in preparing a seed base" to be used in glue made according to my discovery over the time and expense of preparing such seed base used in a basic glue.

A common test to determine the water resistance of glue when panels are made up and pressed is as follows: After the glue has set test pieces of wood panels are sawn so as to permit one square inch of 3-ply panels to be used for break tests, and thereafter are subject to soaking in water for 48 hours. The panels so sawn and soaked are placed in a machin and subjected to a pull which is measured by a scale, and the strength of the glue joint is noted in pounds per square inch. For a test of dry strength a similar method is pursued, except the soaking is omitted.

By means of using Intramine P. C. (without water soluble metallic sulphate) I have succeeded in raising the strength of the glue bond my glue made according to my discovery above the strength of a "basic glue." A basic glue, such as herein described, produces an average dry test pull of about 171.5 pounds, with a minimum of about pounds and a maximum of about 200 pounds. By means of my discovery, by the use of Intramines alone with a basic glue, th dry of about 210 pounds 245 pounds.

Thus there is shown an improvement in the dry test of the glue made according to my discovery of about 60 pounds better than a basic glue, or

an increase of about 35% in dry strength.

The average wet test strength of a basic glue" is about 98.5 pounds, with a minimum of 80 pounds and maximum of about 120 pounds. Glue and a maximum of about made according to my discovery, by the use of Intramines alone in a "basic glue, has an average wet strength of 113.5 pounds, with a minimum of 80 pounds and a maximum of 140 pounds, thus showing an increase of average wet strength of 14%.

Instead of the glue made'according to my discovery by the use of'Intramines alone in a basic glue becoming less strong (as is the case with a basic glue) by the lapse of 30 minutes after being spread, the dry test strength of my glue at 30 minutes was 219 pounds, with a minimum of 185 pounds and a maximum of 265 pounds, and a wet test strength of 128 pounds, with a minimum of 115 pounds and a maximum of 145 pounds. Thus there is shown an increase of dr strength in my glue after the panels are spread 34% plus, and a wet strength of 38%. The result of the tests above given were obtained first by making a basic glue, consisting of the following:

Example 6 An example of blend base glue which will produce superior results is as follows: Pounds Soya bean flour 89.9 Casein 5 Blood albumen 5 Intramine P. C. or Intramine D. X 0.1 to 0.5

Example 7 Another example of blend base glue, such as ,is described in Example 6, above, would be to eliminate from Example 6, 5 lbs. of the blood albumen or casein and correspondingly increase the soya bean flour or peanut flour; or'instead of 5 lbs. blood albumen and 5 lbs. casein, use 10 lbs.

of casein or 10 lbs. blood albumen, or a lesser or viz: Pounds 4 Water at a temperature of about 70 F- About 330 Caustic soda dissolved in 10 lbs of with it for minutes before being pressed of Pounds Soya bean flour 100 Water 360 Caustic soda dissolved in 10 "lbs. of water 8 Lime suspended in 25 lbs. of water -7 Sodium silicate 25 Carbon bisulphide-tetrachloride dope 2 and then by-making an exactly similar basic glue" to which Intramine P. C., in the amount of about 0.15 pound of Intramine P. C. was incorporated, by which addition the glue which I designate as improved glue is produced.

Other examples of glue formulae using my invention of improved glue and method of making same, which I find produces similar superior results to those above mentioned, are as follows:

As a "dry mixture," viz:

Example 1 Pounds Soya bean flour 99 Intramine Y .4. 1

Example 2 Soya bean flour 99.9 Intramine P. C. or Intramine D. X 0.1

Example 3 Soya bean flour 98 Pine oil 1 Intramine Y 1 Example 4 Soya bean fiour 98.9 Pine oil -l 1 Intramine P. C. or Intramine D. X 0.1

Example 5 Soya bean flour 98 Sodium dichromate or sodium phosphate 1 Intramine P. C. or Intramine D. L 0.1 Pine oil 0.9

water About 8 Hydrated lime suspended in 25 lbs. of

water About '7 Sodium silicate About 20 Carbon bisulphide dope About 2 Where Intramine, such as described, is incorporated in the formula of a dry mixture, as

shown in the examples last above mentioned, it may be eliminated therefrom, and may be added to the water at the start, or during the process of mixing. In such examples peanut flour and other proteinous flours, as described herein, may be used instead of soya flour.

The improved glue which I have made by means of incorporating one or more of the Intramines in a basic glue I will hereinafter call my improved glue.

I have found that by means of incorporating into my improved glue from 2.5 pounds to 5 Pounds Soya'bean flour or peanut flour 97.4 Zinc sulphate 2.5 Intramine P. C. or Intramine D. X -1- 0.1

Water at roughly 70 F. (or at summer temperature. The matter of temperature is not essential, but a substantially similar temperature produces a more uniform time for chemical action than would be the case with wide variations in water temperature) 360 Caustic soda dissolved in 10 lbs. of water 8 Lime suspended in 25 lbs. of water 7 Sodium silicate 25 Carbon bisulpl'iide-tetrachloride dope 2 dry and wet strength in my An example of a typical zinc sulphate glue employing a base blend which will produce comparable results is as follows:

Carbon disulphide-tetrachloride dope 2 Another example of zinc sulphate glue employing a blend base would be to eliminate in the above formula 5 pounds of either casein or blood albumen, and correspondingly increase the soya bean flour or peanut flour, or, instead of 5 poundseach of blood albumen and casein use pounds of casein or' 10 pounds of blood albumen, or a lesser or greater number of pounds thereof, and

correspondingly modifysoya bean flour or peanut flour.

A glue made by employing the basic glue using a seed base to which has been added one of the Intramines and zinc sulphate made according to the formula of the foregoing example shows the average dry strength of such glue to be 265 pounds, the average wet strength of such glue to be 150 pounds. For the purpose of comparison, the following table is set forth:

"Basic glue Average dry strength Average wot strength 171.5 pounds 98.5 pounds Basie glue plus Intramines (my "improved glue") 232 pounds 118 pounds Basic glue plus Intramines and zinc sulphate (zinc sulphate glue) 205 pounds 150 pounds In the matter of the dry test strength, my "zinc sulphate glue is approximately 64% plus stronger than the basic glue. In the matter of wet strength my zinc sulphate glue is approximately 51% plus stronger than the basicgluf' In the matter of dry test strength my zinc sulphate glue is approximately 14% plus stronger than my "improved glue. In the matter of wet test strength my-"zinc sulphate glue" is approximately 40% plus stronger than my "improved glue." In addition to the increase in both zinc sulphate glue" over said "basic glue and "improved glue, I find that .my means of employing Intramine in the glue with the zinc sulphate I control the action of the zinc sulphate in the quantities used by me. If zinc sulphate (without the Intramine) in the quantities used by me is used with a "basic glue, its action within the glue causes an erratic and unpredictable result. On some occasions it thickens the glue too quickly for use in ordinary mill practice, whereas, with the combination of Intramine and zinc sulphate with the basic glue, the glue is thinned as compared with basic glue" with zinc sulphate therein, and the end result is uniform and reliable, and the beneflcial effect as pointed out herein is certain and predictable;

My zinc sulphate glue will spread 1000 square feet of 3-ply panels with the use of but from to 24 pounds of seed base," whereas, the "basic glue" requires from 27 to 30 pounds of "seed base to spread 1000 square feet of 3-ply panels. Thus my zinc sulphate glue" requires 6 to 10 pounds less seed base per 1000 square Pounds feet of 3-ply panels than the "basic glue" requires, and effects thereby a great cost saving over basic glue," or about of the cost of seed base. As

there are used in the plywood industry hundredsof tons amonth of seed base glues, and "blend base glues, the aggregate saving by my'improved glues is a very material consideration. My "zinc sulphate glue has the quality of retaining its viscosity practically at a uniform level much longer than a basic glue," thereby increasing its working life and avoiding waste of glue when delay occurs at the veneer plant after mixing the glue in the glue mixer.

The viscosity of my zinc sulphate glue has a range of from 60 to 85 during 3 hours on a MacMichael viscosimeter as compared under like conditions with a basic glue of from 60 to 280 in 85 minutes. The basic glues working life" is limited to about 50 minutes, whereas my "zinc sulphate glue has been used with satisfactory results after standing mixed in the glue pot over night. The increased "working life is important in plant practice, and has long been sought by manufacturers of plywood.

In practicing my invention I prefer to use zinc sulphate because it is commercially readily available, and is likewise low in cost. However, any compound having the characteristics of zinc sulphate in a glue mix may be used with similar results. Among the many equivalents of zinc sulphate in practicing my invention are the sulphates of such metals as aluminum, iron, cadmium, copper, and the like.

The water soluble metallic sulphates which I have discovered improve my improved glue" are designated in-Groups 3, 4 and 5 of the Fresenius System. Of these I find iron sulphate makes the least improvement in my improved glue. For the purpose of defining such water soluble metallic sulphates in these specifications and in the claims I will use the phrase water soluble metallic sulphates of Groups 3, 4 and 5 of the Fresenius System.

When employing zinc sulphate, for example, in

my zinc sulphate glue" I use quantities thereof of 1.5% to 9% of the seed base or blend base and find that a ratioof 2.5 pounds of zinc sulphate to 95 to 100 pounds of seed base or "blend base will yield the numerous beneficial results herein set forth when an Intramine is present in the amount of about 0.1% of the seed base" or blend base, although a greater quantity may be used for an Intramine is fast to lime and the acids and alkali of the glue.

It is understood that these formulae are examples only, and that I may use instead of soya flour varying kinds of vegetable flours containing substantially the amount of protein as above set forth, for example, peanut flour or cotton seed flour, and that I do not confine the scope of my invention to these examples only, as I may vary the proportions of any of the ingredients in either my "improved glue" or in my zinc sulphate glue";

' for example, I may use an alkali salt to replace a part or all of the caustic soda and may use any one of the Intramines as herein described, and may differ the proportions thereof to produce a glue of varying qualities to meet the requirements of the trade and the variations in the quality of the "seed base."

I have found it convenient to mix together, for instance, soya bean flour, Intramines in dry form, and the metal sulphate of Groups 3, 4 and 5 of the Fresenius System "and pine oil, if used," at the same time the seed base is ground, for thus at the glue plant into a glue mixer containing about 360 pounds of water and stirred for from 3 to 5 minutes; thereafter is added the lime suspended ln water, then stirred for approximately 3 minutes; thereafter is added the caustic soda dissolved in water and stirred for-approximately 3 minptes; thereafter is added the sodium silicate and stirred for approximately one minute; thereafter is added carbon bisulphide-tetrachloride dope and stirred for approximately 5 minutes, Then the glue is ready for use, the total mixing time being about 17 minutes, thus shortening the ordinary time of mixing basic'glue" by about 5 minutes.

Whenever any of the Intramines are used in solution I find it preferable, although not imperative, to introduce the same into .the water before seed flour is added.

Other modes of applying th principle of my invention may be employed instead of those explained above, the change being made as regards the details herein disclosed, provided the procedure or ingredients stated, or the equivalents of such stated ingredients or procedure, are employed. The particular order in which the flour and several of the ingredients mixed in the formulas given by me in the making of glue according to my invention may be varied, and it is not necessary that the manufacture of the product be completed in a single operation.

By giving the explanation and illustrations aforesaid, I do not intend to limit or indicate the use of my glue as confined to the application of my glue as explained and illustrated. For a glue made in accordance with the principles of my invention may be used where a glue is desirable having the qualities of my invention.

When I use the term carbon bisulphide tetrachloride dope in this'specification it is to be understood that I mean one of the several agents used in the glue industry under that name. I prefer to use carbon bisulphide-tetrachloride dope as it is readily and cheaply obtainable, and has been quite uniformly used in the basic glues.

A typical carbon bisulphide-tetrachloride dope is comprised of from 50 to 75 parts of carbon bisulphide and from 2 5 to 50 parts of carbon tetrachloride. From 1 to parts of resin, such as rosin, is sometimes used to replace an equal amount of carbon bisulphide. I do not desire to confine myself to the use of carbon bisulphide and tetrachloride dope. Carbon bisulphide may be used alone, or I may use equivalents of carbon bisulphide, for instance, sodium thiocarbonate or potassium xanthate. The carbon tetrachloride used with carbon bisulphide is introduced for the purpose of preventing its ready ignition, and a small portion of resin may be used or not, as the theory of using the rosin is to lessen the escapement of carbon bisulphide fumes in the mixing of the glue, but neither the carbon tetrachloride nor the rosin is essential.

Having described my invention, what I claim and desire by Letters Patent is:

1. An adhesive composition which comprises the reaction product of a proteinaceous glue of at least one of the class consisting of vegetable seed flour of considerable protein content, casein,

soluble 'blood albumin, and a sulphated product of the condensation reaction of fatty acids containing a predominant amount of C12 and C14 acids and monoethanolamine in an amount re-' sulting in an increased spreadability, working life,

strength and water resistance 10f the adhesive, and awater soluble metallic sulphate of Groups 3, 4 and 5 of the Fresenius System in an amount to increase water resistance, strength, spreadability and working life of the resultant adhesive.

2. An adhesive composition which comprises the reaction product of proteinaceous glue of at least one of the class consisting of vegetable seed flour of considerable protein content, casein, soluble blood albumin, and a sulphated product of the condensation reaction of fatty acids containing a predominant amount of C11 and C11 acids and monoethanolamine.

3. An adhesive composition which comprises the reaction product of a proteinaceous glue of at least one of the class consisting of vegetable seed flour of considerable protein content, casein, soluble' blood albumin, and a sulphated product of the condensation reaction of fatty acids containing a predominant amount of C12 and C14 acids and monoethanolamine in the proportion of from 0.05% to 2% of the proteinaceous material in the resultant adhesive.

4. The process of making an adhesive which comprises combining the reaction product of a proteinaceous glue of at least one of the class consisting of vegetable seed flour of considerable protein content, casein, soluble blood albumin, and a sulphated product of the condensationv reaction of fatty acids containing a predominant amount of C12 and C14 acids and monoethanolamine, the proportion thereof being 0.05 pound to 2 pounds in pounds of the proteinaceous material in the resultant glue.

5. An adhesive composition which comprises the reaction product of a proteinaceous glue of at least one of the class consisting of vegetable seed flour of considerable'protein content, casein, soluble blood albumin, and a sulphated product of the condensation reaction of fatty acids con-.- taining a predominant amount'of C12 and C14 acids and monoethanolamine, the proportion being from 0.05% to 2% to 100 pounds of the proteinaceous material in such glue, and from 2 to 5 pounds of a water soluble metallic sulphate of Groups 3, 4 and 5 of the Fresenius System to 100 pounds of the proteinaceous material in theresultant-glue.

6. A process of making an adhesive which comprises combining the reaction product of a proteinaceous glue of at least one of the class consisting of a vegetable seed flour of considerable protein content, casein, soluble blood albumin, and a sulphated product of the condensation reaction of fatty acids containing a predominant quantity of C12 and C14 acids and monosulphated product of-the condensation reaction of fatty acids containing a predominant amount in the resultant of C1: and C14 acids and monoethanolamine, and

from 2 to 5 pounds of a water soluble metallic the resultant glue.

8. An adhesive composition which comprises the reaction product of a 'proteinaceous glue of at least one of the class consisting of a vegetable seed flour of considerable protein content, casein, soluble blood albumin, and a sulphated product of the condensation reaction of fatty acids containing a predominant amount of C1: and C14 acids and monoethanolamine, the proportion being from 0.05% to 2% of 100 pounds of the proteinaceous material in such glue and from 2 to 5 pounds of zinc sulphate to 100 pounds of the proteinaceous material in the resultant glue.

9. An adhesive composition comprising adding to 99.90 pounds of soya bean flour 0.10 pound of a sulphated product of the condensation reaction of fatty acids containing a predominant amount of C12 and C14 acids and monoethanolamine, about 330 pounds of water, 8 pounds of caustic soda dissolved in pounds of water seven pounds of lime suspended in 25 pounds of water,

3, 4 and 5 of Fresenius Sysadding to 87.4

pounds of sodium silicate and 2 pounds of carbon bisulphide.

10. An adhesive composition comprising adding to 97.4 pounds of soya bean flour 0.1 pound of a sulphated product of the condensation reaction of fatty acids containing a predominant amount, of C1: and C14 acids and monoethanolamine, 2.5 pounds of zinc sulphate, about 360 pounds of water, 8 pounds oi caustic soda dissolved in 10 pounds of water, 7 pounds of lime suspended in 25 pounds of water, 25 pounds of sodium silicate and 2 pounds of carbon bisulphide.

11. An adhesive composition which comprises pounds of soya bean flour 5 pounds of casein, 5 pounds blood albumin, 0.1 pound of a sulphated product of the condensation reaction of fatty acids containing a predominant amount of C1: and C14 acids and monoethanolamine, 2.5 pounds of water, 8 pounds of caustic soda dissolved in 10 pounds of water, seven pounds of lime suspended in 25 pounds of water, 25 pounds of sodium cate and 2 pounds oi carbon bisulphide.

DAVIS MILLER WOOD.

zinc sulphate, about 360 pounds of sili- 

